password entry for encrypted container fails due to race condition

[r3cgm]

By using the system 'expect' tool, there is a race condition during the mounting of the encrypted container (via 'tcplay -m') where control has not yet been passed by the child process to STDIN before the parent python process issues the password. This results in the password being displayed directly on the screen, and also prevents the backup from proceeding. This race condition has been solved by introducing a 50ms delay automatically in the Python pexpect library.